promptfoo
diff --git a/‎plugins/promptfoo/src/agent/providers.ts‎
Lines changed: 7 additions & 3 deletions b/‎plugins/promptfoo/src/agent/providers.ts‎
Lines changed: 7 additions & 3 deletions
diff --git a/‎plugins/promptfoo/src/cli.ts‎
Lines changed: 4 additions & 2 deletions b/‎plugins/promptfoo/src/cli.ts‎
Lines changed: 4 additions & 2 deletions
@@ -22,6 +22,7 @@ export interface ChatOptions {
   tools: unknown[];
   maxTokens?: number;
   temperature?: number;
+  reasoningEffort?: 'low' | 'medium' | 'high';
 }
 
 export interface ChatResponse {
@@ -41,11 +42,13 @@ export class OpenAIProvider implements LLMProvider {
   private apiKey: string;
   private model: string;
   private baseUrl: string;
+  reasoningEffort?: string;
 
-  constructor(options: { apiKey?: string; model?: string; baseUrl?: string }) {
+  constructor(options: { apiKey?: string; model?: string; baseUrl?: string; reasoningEffort?: string }) {
     this.apiKey = options.apiKey || process.env.OPENAI_API_KEY || '';
     this.model = options.model || 'gpt-4o';
     this.baseUrl = options.baseUrl || 'https://api.openai.com/v1';
+    this.reasoningEffort = options.reasoningEffort;
 
     if (!this.apiKey) {
       throw new Error('OpenAI API key required. Set OPENAI_API_KEY env var.');
@@ -69,6 +72,7 @@ export class OpenAIProvider implements LLMProvider {
         ...(this.model.startsWith('gpt-5') || this.model.startsWith('o1') || this.model.startsWith('o3')
           ? {}
           : { temperature: options.temperature ?? 0.7 }),
+        ...(options.reasoningEffort || this.reasoningEffort ? { reasoning_effort: options.reasoningEffort || this.reasoningEffort } : {}),
       }),
     });
 
@@ -257,12 +261,12 @@ export class AnthropicProvider implements LLMProvider {
 /**
  * Create provider from string identifier
  */
-export function createProvider(provider: string): LLMProvider {
+export function createProvider(provider: string, options?: { reasoningEffort?: string }): LLMProvider {
   const [type, model] = provider.split(':');
 
   switch (type) {
     case 'openai':
-      return new OpenAIProvider({ model: model || 'gpt-4o' });
+      return new OpenAIProvider({ model: model || 'gpt-4o', reasoningEffort: options?.reasoningEffort });
     case 'anthropic':
       return new AnthropicProvider({ model: model || 'claude-sonnet-4-20250514' });
     default:
 
@@ -27,6 +27,7 @@ async function main() {
     const outputDir = getArg('--output') || getArg('-o') || '.';
     const verbose = args.includes('--verbose') || args.includes('-v');
     const maxTurns = parseInt(getArg('--max-turns') || '30', 10);
+    const reasoningEffort = getArg('--reasoning');
 
     let context: string;
 
@@ -52,7 +53,7 @@ async function main() {
     // Detect format
     const format = detectFormat(context);
     console.log(`Detected format: ${format === 'unknown' ? 'text/description' : format}`);
-    console.log(`Provider: ${providerStr}`);
+    console.log(`Provider: ${providerStr}${reasoningEffort ? ` (reasoning: ${reasoningEffort})` : ''}`);
     console.log(`Output: ${outputDir}`);
     console.log('');
 
@@ -62,7 +63,7 @@ async function main() {
     }
 
     // Create provider
-    const provider = createProvider(providerStr);
+    const provider = createProvider(providerStr, reasoningEffort ? { reasoningEffort } : undefined);
 
     // Run discovery agent
     console.log('Starting target discovery agent...');
@@ -134,6 +135,7 @@ Options:
   --output, -o <dir>     Output directory (default: current dir)
   --provider <provider>  LLM provider (default: openai:gpt-4o)
   --max-turns <n>        Max agent turns (default: 30)
+  --reasoning <effort>   Reasoning effort for GPT-5/o-series (low, medium, high)
   --verbose, -v          Show detailed output
 
 Supported input formats: